Adjustable ladder and scaffold

ABSTRACT

A ladder having one or more of its legs individually extensible so as to enable it to stand or be supported on an irregular surface. The ladder can be converted into a scaffold whose height may be varied utilizing the extensible legs. A standard ladder can be converted for use on irregular terrain by the addition of a novel single leg supported by the lower rung of the ladder and movable therealong.

United States Patent [191 Fleischer I {54] ADJUSTABLE LADDER ANDSCAFFOLD [76] Inventor: Henry Fleischer, l8 Notch Park Road, LittleFalls, NJ.

221 Filed; June 29,1971

[21] Appl. No.: 157,866

[52] U.S. Cl ..182/27, 182/203 [51] Int. Cl. ..E06c l/383, E04g 1'/3O[58] Field of Search ..l82/27, 205, 203

[56] References Cited UNITED STATES PATENTS l,245,073 10/1917 Walter..l82/25 [451 Apr. 3, 1973 476,897 6/1892 Ripp v.182/27 3,071,204 l/l963Piltingsrud 2,152,895 4/l939 Longtin ,.l82/205 Primary Examiner-ReinaldoP. Machado Attorney-Lawrence l. Lerner et al.

[5 7] ABSTRACT A ladder having one or more of its legs individuallyextensible so as to enable it to stand or be supported on an irregularsurface. The ladder can be converted into a scaffold whose height may bevaried utilizing the extensible legs. A standard ladder can be convertedfor use on irregular terrain by the addition of a novel single legsupported by the lower rung of the ladder and movable therealong.

5 Claims, 10 Drawing Figures PATENTEDAPR 3 m5 SHEET 1 BF 2 I NVE NTOR.

HENRY FLEISCHER i'WEWEDAPR 3 I973 SHEET 2 [IF 2 FIG.7

HE N RY FLEISCHER INVIEN'I'OR.

ADJUSTABLE LADDER AND SCAFFOLD BACKGROUND OF THE INVENTION extension legcan be selectively positioned at a:

predetermined vertical position with respect to the ladder leg to whichit is secured to steady the ladder or uneven terrain. However, in eachof these patents, the extension leg is secured to one leg or the other;none of the extension legs being capable of being shifted from one legto the other. U.S. Pat. No. 898,973 has taught the use of verticallyadjustable ladder attachments with respect to both legs of a ladder.U.S. Pats. Nos. 199,922; 1,424,934; and 2,971,602 have taught ladder legleveling devices which include generally semi-circular elements whichare pivoted with respect to the bottommost rung of the ladder in orderto level the ladder on uneven terrain. U.S. Pats. Nos. 1,272,551 and2,663,283 also teach leveling and equalizing support for ladders whichare generally vertically adjustable with respect to the bottom rung ofthe ladder.

Thus, prior art leveling devices have generally been of two classes. Thefirst class of device generally include a vertically adjustablememberrsecured to one or both legs of the ladder; the second classinvolve a semicircular attachment from which the ladder can be pivotedwith respect to unequal terrain. None of the leveling devices taught bythe prior art are movable in a selected horizontal direction between thelegs of the ladder so that one selected leg can be made verticallyadjustable to compensate for uneven terrain with respect to the other.This type of device would allow for attachment to an existing ladder.

Further, none of the prior art leveling devices are useful in adopting aladder for conversation into a scaffold..

FIELD OF THE INVENTION This invention relates to leveling devices forladders, ladders which may be converted into scaffolds, and levelingdevices for a ladder so converted into a scaffold. The devices of thepresent invention are meant to be sold as a separate attachment to bemounted on existing or as an item to be incorporated in the manufactureof ladders.

SUMMARY OF THE INVENTION In the present invention, there are two basicembodiments. The first embodiment is a ordinary step ladder wherein theback legs are each individually extensible to be varied in accordancewith the terrain. The cross members joining the ladder with the backlegs are also adjustable in accordance with the position of the ladder.The cross members are separable from the back legs to become theupstanding-legs of a scaffolding with the ladder portion becoming thehorizontal portion of the scaffolding when erected. The cross membersare substantially equal in length to the back legs of the ladder so thatthey can form equal legs each individually adjustable to the terrain inwhich the scaffolding will be placed. On the side walls of the stepladder rung portion there are placedremovable cross braces which areattachable to the vertical members of the scaffold to provide bracingfor the scaffolding when 1 fully erected.

In the second embodiment, there is provided a single extensible leglongitudinally movable on the bottom rung of a ladder. The extensibleleg is slidable from one side of the rung to the other in accordancewith the needs of the user. This is especially useful for extensionladders wherein the ladder cannot be reversed without creating safetyproblems. The extensible leg attached to the rung of the ladder can beincorporated in the manufacture of the ladder or added to existingladder.

DESCRIPTION OF THE DRAWINGS I FIG. 1 is a perspective view of a stepladder built in accordance with the principles of the present invention.

FIG. 2 is an enlarged showing of one of the cross members of the ladderof FIG. 1.

FIG. 3 is a cross-sectional view of the cross member of FIG. 2 takenalong lines 3-3 thereof.

FIG. 4 is a top plan view of the cross member shown in FIG. 2.

FIG. 5 is a perspective view of the step ladder in FIG. I converted intoa scaffolding.

FIG. 6 is a plan view of one of the crossmembers at tached to the sideleg of FIG. 1.

FIG. 7 is a drawing of a standard ladder to whichhas been attached anextensible leg in accordance with the second embodiment of the presentinvention.

FIG. 8 is an enlarged view of the mounting of the extension leg shown inFIG. 7.

FIG. 9 is a cross-sectional view taken along lines 9- 9 of FIG. 8.

FIG. 10 is an expanded view of the manner in which the attachment shownin FIG. 7-9is made to the lowermost rung of a ladder.

DETAILED DESCRIPTION In FIG. 1, there is shown a step ladder built inaccordance with the principles of the present invention generallydesignated by the numeral 10. Step ladder 10 comprises a front ladderportion 12, a back leg portion 14 and cross member 16. The front ladderportionl2 comprises two front legs 18 and 20 joined by rungs 22. Thelegs 18 and 20 have each connected at the bottom end thereof frontcleats 24 and 26 respectively. At the top of front ladder portion 12there is provided a platform 28 .pivotally connected to legs 18 and 20and spring biased into place by means of the spring 30.

The back leg portion 14 consists of two back legs 32 and 34 joined attheir upper ends to front legs 18 and 20 respectively. Each of the backlegs 32 and 34 has, at its lower end, ratchet connected telescopingextensional legs 36 and 38 respectively. The back legs 32 and 34 arejoined by a cross member 44 to give lateral stability to the back legportion 14. The extension legs 36 and 38 may be moved with respect tothe back legs 32 and 34 by means of ratchet locking means 46 and 48which engage teeth 50 and 52 respectively on the extension legs 36 and38. The operation of the ratchet members 46 and 48 will be described indetail hereinafter.

The cross member portion 16 consists of two cross member legs 54 and 56joined by a bar 58. Each of the cross members legs 54 and 56 has atelescoping extension leg 60 and 62. The legs 60 and 62 have hooks 64and 66 which engage pins 68 and 70 on the inside surface of back legs 32and 34 respectively. Cleats 72 and 74 are pivotally connected to theends of the extension legs 60 and 62; and at the other end of crossmember 16, legs 54 and 56 are pivotally connected to the bottom ends ofthe siding of ladder front legs 18 and 20. It will be appreciated thatthe connection of said cross member portion to the front and backportion of the ladder may be reversed.

The legs 60 and 62 are made extensible with respect to cross member legs54 and 56 by reason of ratchet locking means 76 and 78 respectivelywhich engage teeth 80 and 82 on extension legs 60 and 62 respectively.Ratchet member 76 will be described in detail, it being understood thatit is similar in operation to ratchet members 78, 46 and 48.

With further reference to FIGS. 2 and 3 ratchet member 76 includes ahandle 84 pivotally mounted between side plates 86 and 88 on pin 90.Handle 84 has a pin 92 therethrough to which is linked (by link 93) awedge shaped tooth 94 which engages the teeth 80 of extension leg 60.Movement of handle 84 to the position shown in dotted lines at 84 liftswedge shaped tooth 94 out of the tooth 80 and allows the extension leg60 to telescope inwardly or outwardly with respect to the hollow leg 54.Upon movement of handle 84 back to the solid line position shown in FIG.2, the wedge shaped tooth 94 is wedged into position within teeth 80locking the leg 60 in place.

It can thus be seen that the step ladder can have the length of one orboth of its back legs 32 and 34 extended by moving the extension legs 36and 38 downwardly or upwardly with respect to it associated hollow backleg 32 or 34. It is thus possible to level the ladder 10 with respect tothe irregularities in the ground surface. It is further possible to varythe span between front and back by varying the length of the legs 54,60; 56, 62 of the cross member 16.

Each of the legs 18 and 20 carries thereon a pair of cross braces 96, 98and 100, 102 respectively. Cross brace 96 is shown in FIG. 6 and has ahole 104 on one end thereof and a hook 106 at the other end thereof. Thehole 104 in braces 96 and 98 is placed over a pin 108 located on theouter surface of the bottom end of leg 18. The hook 106 of braces 96 and98 is placed over a pin 110 at the upper end of leg 18. Similarly, thecross braces 100 and 102 are mounted on pins 112 and 114 positioned onthe outer surface of leg 20.

When the step ladder 10 is intended to be used as a scaffolding, this isaccomplished in the manner shown in FIG. 5. That is, the cross members116 are lifted off the pins 68 and 70 and extended downwardly. The crossbraces are mounted as follows: cross brace 96 has its hole 104 mountedon a pin I07 and its hook end connected over a pin 116 on the innersurface of back leg 32. Brace 98 is connected between pin 118 on theinner surface of leg 54 and pin 120 on the outer surface of leg 32.Brace 100 is connected between pin 122 on the outer surface of leg 34and pin 124 on the surface of leg 56. Finally, brace 102 is connectedbetween pin 123 on the outer surface of leg 56 and pin 126 on the innersurface ofleg 34.

Thus, in place, the scaffolding shown in FIG. 5 is rigid, fully braced,and is capable of being placed on any irregular surface by merelyadjusting the height of the individual legs of the scaffold utilizingthe ratchet locking means 76, 78, 46 and 48. Thus the step ladder 10 hasbeen shown to be adjustable both as a step ladder and a scaffold and maybe easily converted from one to the other. The hooks 64 and 66 haveproved to be detatchable connecting means attachably connected to theback legs and pivotally connected to the ladder legs and thus easilyconvertable from the ladder into the scaffold arrangement. The platform28 is spring biased out of position, and the cleats 24 and 26 aregravity biased out of position so as not to interfere with the use ofthe ladder of the scaffolding. If desired a board can be supported onthe ladder when used as a scaffolding.

In FIG. 7-10, there is shown a second embodiment of the presentinvention. In FIG. 7, there is shown a ladder 130 having side legs 132and 134 joined by rungs 136. The lowermost rung 138 of the rungs 136 isadopted to have connected thereto the extension attachment of thepresent invention generally designated by the numeral 140. Although theladder 130 has been shown as a simple one piece ladder, the invention isespecially useful for extension ladders of the type generally known andthe invention will be so described. As shown, the extension attachment140 is adopted to give additional length to one of the legs 132 or 134so that the ladder may stand on an uneven terrain such as a hill in themanner shown in FIG. 7.

The extension attachment 140 consists of a cross member 142 fixedlysecured between the legs 132 and 134 by screw members l44'and 146. Screwmember 144 is secured to the leg 132 so that the cross member 142 is ina fixed position immediately below the lowest rung 138 and spacedtherefrom by means of a spacing means 148 (FIG. 10). The screw 144passes through a hole 150 in the side wall of the leg 132 which hole 150can be drilled in the situation where leg attachment 140 is to be addedto an existing ladder, or hole 150 can be prepunched in the situationwhere a ladder is being manufactured with the adjustable leg attachment140. Other means for attaching the leg attachment 140 can be utilizedwithin the scope of the present invention, such as clamp means or thelike.

The extensible leg attachment 140 further includes an extensible leggenerally designated by the numeral 152. The extensible leg 152comprises an upper hollow leg154, a middle hollow leg 156 and a lowerleg 158 with a suitable pivotally connected cleat 160 at the bottomthereof. The lower leg 158 has teeth 161 thereon which are engaged bysuitable ratchet member 162 mounted at the lower end of middle legmember 156. Ratchet 162 controls the relative vertical position of lowerleg 158 with respect to middle leg 156. Middle leg 156 has teeth 164 onthe outer surface thereof. The upper hollow leg 154 has a suitableratchet member 166 mounted at the lower end thereof for engaging theteeth 164 of middle leg 156. This allows middle leg 156 to be verticallypositioned relative to upper leg 154. The use of the three legs 154, 156and 158 provides a variation in the overall length of the extensible leg152.

The extensible leg 152 has, at its upper end, inwardly directed flanges168 and 170, which flanges are fitted within horizontally extendinggrooves 172 and 174 in cross member 142. The position of the leg 152relative to the cross member 142 is determined by the operator by merelysliding leg 152 along leg 142 with the flanges 168 and 170 fittingwithin the grooves 172 and 174. When a desired position is reached, asuitable locking cam 176 is locked into position in the manner shown inFIG. 7. It is thus possible, utilizing a single adjustable leg 152 toextend one or the other of the legs 132 or 134 as desired. Bycompressing the leg 152 to its shortest position, the ladder 130 can beused in the ordinary manner since leg 152 would then have alength-merely equal to the length of the ladder leg 132.

I claim as my invention 1. A combination extensible ladder and scaffoldcomprising:

a ladder portion having ground engaging means at the bottom end thereof;a first leg portion having ground engaging means at the bottom endthereof, means for pivotally connecting said ladder portion to saidfirst leg portion at the top ends thereof, a second leg portionpivotally connected to the bottom end of one of said ladder portion andfirst leg portion and having a free end detachably connected to theother of said first leg portion ladder portion, said free end havingground engaging means at the end thereof,

detachable scaffold bracing means detachably connectable between saidsecond leg portion and said first leg portion to form a scaffold, andsaid first and second leg portions having extensible legs, whereby in afirst position an extensible ladder is formed with said second legportions bracing said ladder portion and said first leg portion, and ina second position an extensible scaffold is formed with said detachablescaffold bracing means bracing said first and second leg portions in aparallel upright position. 1 I t 2. The combination extensible ladderand scaffold of claim 1 wherein said one of said ladder portion andfirst leg portion is said ladder portion;

and said other of said first leg portion and ladder portion is saidfirst leg portion. 3. The combination extensible ladder and scaffold ofclaim 1 wherein said first leg portion has two extensible legsindependently extensible relative to each other.

4. The extensible ladder and scaffold of claim l wherein saiddetatchable scaffold bracing means includes cross members detatchablyconnected to the side wall of said front ladder portion when saiddetatchable scaffold bracing means are not used to form a scaffold.

5. The combination extensible leg and scaffold of claim 1 wherein saidfirst leg portion includes hollow legs with said extensible first legportion legs being telescoped within said hollow legs andratchetmeansfor locking said extensible legs into a fixed positionrelative to said hollow legs.

1. A combination extensible ladder and scaffold comprising: a ladderportion having ground engaging means at the bottom end thereof; a firstleg portion having ground engaging means at the bottom end thereof,means for pivotally connecting said ladder portion to said first legportion at the top ends thereof, a second leg portion pivotallyconnected to the bottom end of one of said ladder portion and first legportion and having a free end detachably connected to the other of saidfirst leg portion ladder portion, said free end having ground engagingmeans at the end thereof, detachable scaffold bracing means detachablyconnectable between said second leg portion and said first leg portionto form a scaffold, and said first and second leg portions havingextensible legs, whereby in a first position an extensible ladder isformed with said second leg portions bracing said ladder portion andsaid first leg portion, and in a second position an extensible scaffoldis formed with said detachable scaffold bracing means bracing said firstand second leg portions in a parallel upright position.
 2. Thecombination extensible ladder and scaffold of claim 1 wherein said oneof said ladder portion and first leg portion is said ladder portion; andsaid other of said first leg portion and ladder portion is said firstleg portion.
 3. The combination extensible ladder and scaffold of claim1 wherein said first leg Portion has two extensible legs independentlyextensible relative to each other.
 4. The extensible ladder and scaffoldof claim 1 wherein said detatchable scaffold bracing means includescross members detatchably connected to the side wall of said frontladder portion when said detatchable scaffold bracing means are not usedto form a scaffold.
 5. The combination extensible leg and scaffold ofclaim 1 wherein said first leg portion includes hollow legs with saidextensible first leg portion legs being telescoped within said hollowlegs and ratchet means for locking said extensible legs into a fixedposition relative to said hollow legs.